NASA has cut all ties with Russia's space programme over the crisis in Ukraine, apart from maintaining the International Space Station.

The US space agency had repeatedly said that it wouldn't be taking any action over the situation between Ukraine and Russia, but it reversed its decision, saying in a statement overnight that it would be suspending most of its engagements with Russia. The only exception is the "safe and continuous operation" of the space station, for which it will remain in contact with Roscosmos.

NASA employees will no longer be able to travel to Russia or invite their Russian counterparts to the US and will be forbidden from emailing or conferencing with them as well because of Russia's actions in Ukraine, according to a memo sent to staff.

The leak of the memo yesterday prompted a statement from NASA that criticised Congress for making the agency so reliant on its Russian partners. Since the last of the space shuttles retired from service after Atlantis' last flight in July 2011, NASA has depended on Russia's Soyuz capsules to ferry 'nauts to and from the ISS.

The growing capabilities of Elon Musk's SpaceX firm, already working for NASA on cargo drops at the station, could give the agency a way onto the ISS in the future, but it also wants its own spaceships.

"NASA is laser focused on a plan to return human spaceflight launches to American soil, and end our reliance on Russia to get into space," the agency said in its statement.

"This has been a top priority of the Obama Administration’s for the past five years, and had our plan been fully funded, we would have returned American human spaceflight launches – and the jobs they support – back to the United States next year.

"With the reduced level of funding approved by Congress, we’re now looking at launching from US soil in 2017. The choice here is between fully funding the plan to bring space launches back to America or continuing to send millions of dollars to the Russians. It’s that simple. The Obama Administration chooses to invest in America – and we are hopeful that Congress will do the same.﻿"

Just last week, the agency had said that it didn't expect Russia's annexation of Crimea to impact its cooperation with the country. But since then, other US agencies have been told to stop contact with Russia and NATO has suspended all civil and military cooperation with the country in protest. ®